Kansai University, Teijin develop world’s first piezoelectric fabrics for wearable devices

Piezoelectricity is the ability of certain dielectric materials to generate an electric charge in response to mechanical stress. It also has the opposite effect – the application of electric voltage produces mechanical strain in the materials. Both of these effects can be measured, making piezoelectric materials effective for both sensors and actuators.

In 2012, Kansai University and Teijin developed a flexible, transparent piezoelectric film by alternately laminating PLLA and optical isomer poly-D-lactic acid (PDLA). This latest all-new wearable piezoelectric fabric is the newest application of this technology.

The fabrics comprise a piezoelectric poly-L-lactic acid (PLLA) and carbon fiber electrode. Plain, twill and satin weave versions were produced for different applications: plain weave detects bending, satin weave detects twisting, and twill weave detects shear and three-dimensional motion, as well as bending and twisting.

The sensing function, which can detect arbitrary displacement or directional changes, incorporates Teijin’s weaving and knitting technologies. The function allows fabric to be applied to the actuator or sensor to detect complicated movements, even three-dimensional movements.

The new piezoelectric fabric was introduced at the 1st Wearable Expo, the world’s largest wearable devices and products exhibition, which was held last week at the Tokyo International Exhibition Hall (Tokyo Big Sight) in Japan.

Kansai University and Teijin will continue working on ideal weaves and knits for fabric applications that enable elaborate human actions to be monitored simply via clothing worn by people. Such applications are expected to contribute to the evolution of the Internet of Things (IoT) in fields ranging from elderly care to surgery, artisanal techniques and even space exploration. (KL)

http://www.teijin.com.